Plastic industry

Metal contamination can damage your injection moulding machines, extruders, sieves, mixers and grinders, moulds, dies or other machine components.
This leads to a reduction in quality and production downtime.

Magnets prevent this metal contamination and remove iron parts from all types of plastics.

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The cause of metal contamination

Plastics are supplied in granulate form, powder, or chips. This involves both recycled, as well as newly produced raw materials.

It should not contain unwanted metal or foreign bodies.

The contamination can come from a variety of sources. For example, wear or damage to the machine park during the processing.

Or metal particles that were already mixed in the original products in the recycled raw material and were not, or not properly removed.

Magnetic filtering
magnetic separator for plastics

The consequences of metal contamination

Possible consequences of metal contamination or foreign bodies in plastics include:

* production downtime
* machine damage
* product rejection
* undesirable product characteristics of -
despite the contamination – approved products

For example, consider metal contamination in a transparent water bottle or in a pacifier: the contamination can be minor, the consequences possibly disastrous.

Magnetic filtering
plastic pacifier without metal contamination

The Process

Injection moulding, extrusion, vacuum or pressure deformation and rotation moulding are the most common processes for plastics or thermoplastics. Unwanted metallic parts in plastics may cause clogging of the nozzle or spray openings.

Minimal nozzle thickening completely distorts the dosing of the plastic, which in the worst case scenario will result in the rejection of a whole batch of products.

In addition, in the case of a blockage, the manufacturer needs to dismantle and clean the blocked nozzle or - in the worst case scenario – replace it in its entirety. This means a few hours or longer of production downtime.

In some cases, contamination does not result in a blockage of the injectors, but slips in between the pump and nozzle, and finally ends up in the finished product.

The contaminated batch is placed in quarantine for further investigation. This helps determine the cause which prevents future occurrences. In addition to the additional costs of the investigation, it may also result in a product or even entire batch being rejected.

Getting metal out of plastics

A magnetic filter at strategic locations in the manufacturing process not only detects contamination but immediately purifies the raw material.

This prevents production downtime, machine damage, product rejection or undesired product characteristics.

Goudsmit eddy current separators are particularly well suited to plastics recycling, including PET bottles.

Cleanflow magnets
easy cleanflow magnet for plastics

More information ?

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